The same will also apply to your new tyres as the rear wheels have negative camber built in and this punishes under inflated tyres.

AlanQS, do you know where to find authoritative tyre pressures for non-RFT's? I'm guessing that the plate on the car door applies only to the OEM Bridgestones?

I've replaced the OEM's with Conti 5P's, and am running 34 front 36 rear after much faffing about - but I've no clue if this is best for longevity (the tyres, not mine!). This is on 19 inch 225/35 and 255/30's.